Differential helical chute



March 11, 1930. R. F. WOOD ET AL 7 1,750,081

DIFFERENTIAL HELIGAL CHUTE Filed Sept. 13. 1928 2 Sheets-Sheet l WWWMarch 11, 1930. R. F. WOOD ET AL DIFFERENTIAL HELICAL GHUTE Filed' Sept.13, 1928 2 Sheets-$heet 2 v Z. @ZHeoZler Patented Mar. 11, 1930 UNITEDPATENT OFFICE meat essm; EELIQAL GHITTE."

Application filed; September 13, 1923, Serial no, 305,793,

Thisinvention relates to an improved-type of chute designed for thepurpose of delivering free flowing materials at designated heights.

The primary object of this invention is to provide a lowering chutedesigned to permit materials to be taken therefrom atvarious heights anddistributedto suitablereceiving bodies.

Another objectof the invention i-s-to provide a substantially helicalchute made up of a series of spaced superposed substantially helicalleaves in whichthe lower edge of one leaf overlies and is spaced fromthe upper edge of the next lowerleaf for thepurposeof permittingtheintroduction of" one end ofa straight chute at any pointto; facilitatelateral distribution of material, the openings or spaces between theleaves further being effective and allowing the material to run freefrom the chute in the event that any one of the lower leaves becomesblocked as a re suit of a clogging of the lower lip of that leafiAnother object ofthe invention is to provide a lowering chute made up ofa series of" spaced superposed: helical leaves in which the pitch orrate of drop of the surface of the leaves is variable as a result ofwhich a proper velocity of deli-very of the material is obtained byselecting a proper rate of change in the pitch of the leaves.

As an example, the top leaf of the series 5 may have a pitch ofsubstantially 45 upwardly.

Thebottomi leaf might havea pitch ofonly the intermediate leaves beinggraded accordingly between these pitches. A more or less uniformvelocityof the flowing material is "thus maintained;

The i nve-ntion will be best understood from.

a1 consideration of'the; following detailed description taken inconnection with the accompanyingdrawingswforming part ofthisspecification, with the understanding, however,

thatthe invention isnotconfine d to any strict conformity with theshowing ofthe drawings but may be changed or modified so long as suchchanges or modifications mark noinateri-al departure from the salientfeatures of the invention as expressed in the appended claims: i

In the drawings:

Figure 1 is a side elevation of the device constructed in accordancewith our. inventlon;

Figure 2 is aplan view of the chute;

Figure 3 is a detail elevation of'one of the leaves particularlyillustrating the supporting means for the same Figure 4 is a detailsection illustratingthe relation of the lower or dischargeed ge ofonechute section with the upper or receiving edge of the next lowersection, the position of the ordinary straight chute being illus tratedin dotted lines;

Figure 5 is a View of' a blank of material from which the sections areformed.

Referring to the drawings in detail, the numeral 1 indicates averticalupwardly tapering shaft upon which the leaves making up thechute structure are mounted, this shaft being positioned in any suitablelocation as for example beneath a coal trestle, upon which, at the upperend of the shaft, 7 may be constructed a suitable hopper 2 for directingmaterial downwardly on to the chute structure.

The chute is made up of a series of leaves 3, each of which is ofsubstantially helical design and mounted upon and with the shaftextending through the longitudinal center thereof. These leaves areoriginally of semicircular design, each being provided with an eccentricrecess 4, thus forming a narrow edge or lip. 5. anda relatively wideedge or lip 6.

When the leaves are placed in position upon the shaft in the inannershown the wide edge of the lip 5 is positioned abovethe narrow edge andas will be readily seen, after a series of these leaves have. beendistributed longitudinally on the shaft in superposed spaced relationwith the lower or narrow edge of one leaf substantially directly abovethe wide edge of the next lower leaf, the result is a brokensubstantially helical chute.

Due to the method of securing the leaves about a tapered shaft it willbe readily seen that the pitch of the upper ones of the leaves will besharper than that of the lower leaves so that a gradual decrease in thepitch of the chute as a whole is obtained.

While the blades may be mounted upon the shaft 1 in a number ofdifferent ways, the preferred method of mounting them is by the use ofthe elongated bolts 7.

These bolts are designed to extend through suitably formed passages inthe shaft leaving an extended portion to project along the under face ofthe blade, at an adjacent edge of the same, the extended portion beingsuitably secured to the blade as by welding or in any other desiredmanner.

Due to the method of mounting the leaves, it will be seen that astraight chute of the character indicated by the numeral 8 may have oneend inserted between any pair so that material being lowered by thechute may be conducted laterally to a receiver such as a vehicle, aportion of the body of which is shown in dotted lines and indicated bythe numeral 9. It will also be seen that in the event that the materialclogs the outlet of the lowest leaf, the opening between the same andthe next higher leaf will afford an effective outlet for the material,thus assuring positive action and keeping the chute above the cloggedpoint free and in operation.

The leaves are of a shape which it is believed will accommodate the flowand prevent material from spilling over the sides thereof, one of theadvantages of this construction being that these leaves may be made in amanner that will not require the extreme refinement of slope which isnecessary forthe efiicient operation of a so-called spiral. Likewise thecost of manufacture will be reduced over that of chutes of thisapproximate form now in use. In practice the slope of any leaf may bereadily determined and if not found entirely effective it may be readilyadjusted without affecting any of the other leaves making up thecomplete structure.

' By the use of the tapered shaft, economy in construction is secured asthe leaves may be cut uniformly but when placed in position upon theshaft the desired differential of gradient can be secured, that is, thehelical curvature of the lower leaves will be less sharp than that ofthe upper leaves because of the increased'diameter'of the shaft whichthey must surround.

From the foregoing description, it is believed to be apparent thata'chute constructed not wish to limit ourselves to these details for itis apparent that supporting means may be provided at the outer peripheryof the leaves and also that other means may be em ployed for securingthe leaves to the shaft. It is also apparent that the leaves may be ofvariable dimensions and that they may be formed to the required pitchfor use upon straight shafts if desired instead of depending entirelyupon the shaft tapered for giving the desired pitch to the leaves.

Having described our invention, what we claim is 1. A chute comprising aseries of spaced superposed substantially helical leaves each having abroad end and a relatively narrow end, and means for supporting the samein operative position.

2. A chute comprising a series of spaced superposed substantiallyhelical leaves arranged with the lower end edge of one leaf adjacent andvertically spaced from the upper end edge of the next lower leaf, andmeans for supporting the leaves in position.

3. A chute, comprising a supporting shaft, and a series of substantiallyhelical leaves carried by and formed about said shaft, said leaves beingarranged in superposed relation with the lower end edge of an upper leafarranged adjacent the upper end edge of a lower leaf.

4. A substantially helical chute broken at intervals to permit of theinsertion between certain convolutions of one end of a lateral lead-offchute.

5. A chute of the character described, comprising a vertical shaft, anda series of spaced superposed eccentrically recessed leaves deformed toa substantially helical design receiving the shaft in the recessesthereof, said eccentric positioning of the leaf recess providing theleaf with a relatively broad and a narrow lip, the narrow lip of oneleaf dis- 1chafrging on to the broad lip of the next lower 6. A chute ofthe character described, comprising a vertical shaft, and a series ofspaced superposed eccentrically recessed leaves deformed to asubstantially helical design receiving the shaft in the recessesthereof, said eccentric positioning of the leaf recess providing theleaf with a relatively broad and a narrow lip, the narrow lip' of oneleaf discharging on the broad lip of the next lower leaf, said shaftbeing ofupwardly tapering formation giving to the leaves pitches ofdownwardly decreasing sharpness.

7 The herein described method of decreasing the pitch of a series ofspaced superposed substantially helical leaves assembled to form aspiral lowering chute consisting in forming a central supporting shaftof upwardly L5 tapering design and securing the recessed straight edgesof a series of substantially semi-circular bodies, deformed to asubstantially helical design, to the surface of the shaft.

In testimony whereof We hereunto affix ou signatures.

ROBERT F. WOOD. ERNEST A. HECKLER.

